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Final Report on Site Selection ProcessDoc Ref: 7.05

Volume 14APFP Regulations 2009: Regulation 5(2)(q)

Box 47 Folder A January 2013

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14

Thames Tideway Tunnel Thames Water Utilities Limited

Application for Development ConsentApplication Reference Number: WWO10001

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Thames Tideway Tunnel

Final Report on Site Selection Process

List of volumes Volume 1: Main report Volume 2: Background papers

1. Site selection methodology paper (Summer 2011) 2. Site selection background technical paper (Summer 2011)

Volume 3: Acton Storm Tanks Volume 4: Hammersmith Pumping Station Volume 5: Barn Elms Volume 6: Putney Embankment Foreshore (formerly Putney Bridge Foreshore) Volume 7: Dormay Street (formerly Bell Lane Creek) Volume 8: King George’s Park Volume 9: Carnwath Road Riverside (formerly Barn Elms) Volume 10: Falconbrook Pumping Station (formerly Bridges Court Car Park) Volume 11: Cremorne Wharf Depot (formerly Cremorne Wharf Foreshore) Volume 12: Chelsea Embankment Foreshore Volume 13: Kirtling Street (formerly Tideway Walk) Volume 14: Heathwall Pumping Station (formerly part of Tideway Walk) (this document) Volume 15: Albert Embankment Foreshore Volume 16: Victoria Embankment Foreshore Volume 17: Blackfriars Bridge Foreshore Volume 18: Chambers Wharf (formerly King’s Stairs Gardens) Volume 19: King Edward Memorial Park Foreshore Volume 20: Earl Pumping Station Volume 21: Deptford Church Street (formerly Borthwick Wharf Foreshore) Volume 22: Greenwich Pumping Station Volume 23: Abbey Mills Pumping Station

Final Report on Site Selection Process i Volume 14: Heathwall Pumping Station


Final Report on Site Selection Process ii Volume 14: Heathwall Pumping Station

Thames Tideway Tunnel

Final Report on Site Selection Process Volume 14: Heathwall Pumping Station (formerly

part of Tideway Walk)

List of contents

Page number

1 Introduction ...................................................................................................... 1

1.1 Introduction to the Thames Tideway Tunnel project ................................ 1

1.2 Introduction to this volume ....................................................................... 1

1.3 Type of site .............................................................................................. 2

1.4 Site selection process .............................................................................. 2

2 Phase one consultation preferred CSO site: Site selection process ......... 5

2.1 Introduction .............................................................................................. 5

2.2 Assessment of the long list sites .............................................................. 5

2.3 Assessment of draft short list sites .......................................................... 6

2.4 Assessment of the final short list sites ..................................................... 8

2.5 Phase one consultation preferred site ................................................... 11

3 Phase two consultation preferred CSO site: Scheme development and site selection process .................................................................................... 13

3.1 Introduction ............................................................................................ 13

3.2 Summary of phase one consultation feedback ...................................... 13

3.3 Back-check process .............................................................................. 14

3.4 Phase two consultation preferred site .................................................... 17

4 Post phase two consultation: Review and confirmation of proposed CSO site for Section 48 publicity ........................................................................... 19

4.1 Introduction to the review....................................................................... 19

4.2 Summary of phase two consultation feedback ...................................... 19

4.3 Consideration of project design or new information ............................... 20

4.4 Proposed site for Section 48 publicity .................................................... 20

5 Post Section 48 publicity: Review and final selection of CSO site for the application ...................................................................................................... 21

5.1 Introduction to the review....................................................................... 21

5.2 Summary of Section 48 publicity feedback ............................................ 21

5.3 Consideration of project design or new information ............................... 21

5.4 Final review of shortlisted CSO sites ..................................................... 22

Final Report on Site Selection Process iii Volume 14: Heathwall Pumping Station

5.5 Selected site for the application ............................................................. 22

Appendix 1 .............................................................................................................. 25

Appendix 2 .............................................................................................................. 27

Appendix 3 .............................................................................................................. 29

Appendix 4 .............................................................................................................. 31

List of tables

Page number Table 1.1 Summary of sites identified at each phase of the pre-application process 1

Table 2.1 Long list to draft short list SSMP Table 2.2 assessment ............................ 6

Table 2.2 Draft short list to final short list SSMP Table 2.3 assessment .................... 7

Table 2.3 Preferred site and use for phase one consultation................................... 12

Table 3.1 Long list to draft short list SSMP Table 2.2 assessment .......................... 15

Table 3.2 Draft short list to final short list SSMP Table 2.3 assessment .................. 16

Table 3.3 Preferred site and use for phase two consultation ................................... 18

Table 4.1 Proposed site and use for Section 48 publicity ........................................ 20

Table 5.1 Selected site and use for the application ................................................. 23

Final Report on Site Selection Process iv Volume 14: Heathwall Pumping Station

1 Introduction

1 Introduction

1.1 Introduction to the Thames Tideway Tunnel project 1.1.1 At present, untreated sewage mixed with rainwater (combined sewage)

regularly overflows into the tidal reaches of the River Thames from London’s Victorian sewerage system via combined sewer overflows (CSOs).

1.1.2 Combined sewage discharges must be reduced in order to comply with relevant wastewater legislation. The primary objective of the proposed Thames Tideway Tunnel project (the ‘project’) is to control discharges from CSOs in order to meet the requirements of the European Union’s Urban Waste Water Treatment Directive (91/271/EEC) (UWWTD) and the related United Kingdom legislation.

1.1.3 The Environment Agency has identified 34 ‘unsatisfactory’ CSOs that the project needs to address. The project would control CSO discharges by intercepting and diverting combined sewage flows into a new storage and transfer tunnel. The ‘main tunnel’ would run from west London to Abbey Mills in the east where it would connect to the Lee Tunnel. The Lee Tunnel would then transfer the flows to Beckton Sewage Treatment Works for treatment.

1.2 Introduction to this volume 1.2.1 The Site selection methodology paper states that the project team shall

produce a final report that sets out the site selection process in full. This Final Report on Site Selection Process was prepared for that purpose. Volume 1 of this report explains our approach to identifying and determining the sites required to construct and operate the project and includes a glossary of relevant terminology. Volume 2 comprises the complete Site selection methodology paper and Site selection background technical paper, which were the main documents that guided the site selection process. Volumes 3 to 23 describe the site selection process for each of the sites considered on the Abbey Mills route.

1.2.2 This volume sets out the site selection process that was followed to identify the most suitable site to intercept the Heathwall Pumping Station and South West Storm Relief CSOs at each phase of the pre-application process. This is summarised below in Table 1.1.

Table 1.1 Summary of sites identified at each phase of the pre-application process

Phase Site name Phase one consultation Tideway Walk – combined main

tunnel and CSO site

Phase two consultation Heathwall Pumping Station – CSO interception only

Final Report on Site Selection Process 1 Volume 14: Heathwall Pumping Station

1 Introduction

Phase Site name Section 48 publicity Heathwall Pumping Station –

CSO interception only

Submission of the application Heathwall Pumping Station – CSO interception only

1.2.3 This volume is structured as follows:

a. This section describes the type of site needed and summarises how the Site selection methodology paper was applied at each stage of the pre-application process.

b. Section 2 explains how we identified our preferred CSO site for phase one consultation.

c. Section 3 details of the back-check assessments and reasons why we changed our preferred site for phase two consultation.

d. Section 4 describes the post phase two consultation site selection review and how we confirmed our proposed CSO site for Section 48 publicity.

e. Section 5 describes the post Section 48 publicity site selection review and confirms our selected CSO site for the application.

1.3 Type of site 1.3.1 We need a site to intercept the local combined sewer overflows (CSOs),

known as the Heathwall Pumping Station and South West Storm Relief CSOs, and to connect them to the main tunnel.

1.4 Site selection process 1.4.1 All potential sites were identified in accordance with our Site selection

methodology paper, which involved a ‘sieving’ approach that commenced with the identification of all potentially suitable areas of land (excluding concentrated residential sites and World Heritage Sites). CSO sites also needed to be as close to the relevant existing sewer as practicable; therefore we followed a localised optioneering approach to identify potentially suitable sites in the vicinity of each sewer. The sites went through levels of increasingly detailed assessments. All the assessments were informed by a multidisciplinary approach that took account of engineering, planning, environmental, community and property considerations and our teams’ professional judgement.

1.4.2 Prior to phase one consultation, we applied our multidisciplinary sieving approach to all the assessments outlined in the Site selection methodology paper (summarised at paragraph 2.1.2) for all three main tunnel route options under consideration at this stage of the pre-application process. This process is set out below in Section 2.


1 Introduction 1.4.3 Following phase one consultation, we reviewed the sites and decided to

carry out a ‘back-check’ in order to review the preferred and shortlisted sites prior to phase two consultation. This back-check involved a repeat of each relevant stage of our site selection process in order to reconsider which site would be the most suitable to intercept the CSO site. The back-check utilised the same multidisciplinary approach that we followed prior to phase one consultation. The results of this back-check superseded all previous assessments undertaken prior to phase one consultation and reported in Section 2, except where noted. The back-check process is set out in Section 3.

1.4.4 Following phase two consultation, we reviewed the possible CSO sites. This involved re-checking the selection of sites identified to be most suitable to intercept each CSO associated with the proposed Abbey Mills route in order to confirm the proposed CSO sites for Section 48 publicity. This process is set out below in Section 4.

1.4.5 Following Section 48 publicity, we reviewed our proposals having regard to the feedback from the publicity exercise. The purpose of this review was to define and decide any changes to our final proposals for the application. Every proposed CSO site on the Abbey Mills route was re-checked in order to confirm its selection for the application. This process is set out in Section 5.


1 Introduction



2 Phase one consultation preferred CSO site: Site selection process


2.1 Introduction 2.1.1 This section explains how the Site selection methodology paper was

implemented in order to select the preferred CSO site for phase one consultation. This stage took place from Spring 2009 to Summer 2010.

2.1.2 In order to arrive at the preferred site for phase one consultation, the site selection process comprised: a. identification of sites for inclusion on a long list b. assessment of sites on the long list to create a draft short list c. assessment of the draft shortlisted sites to create a final short list d. preparation of detailed site suitability reports for each final shortlisted

site e. a multidisciplinary optioneering workshop to compare the suitability of

each of the shortlisted sites and identify the preferred CSO site to intercept the Heathwall Pumping Station and South West Storm Relief CSOs for phase one consultation.

2.1.3 The assessments described in this section were based on the information available at the time and the related stage in the pre-application process.

2.1.4 A plan that illustrates all the sites considered for the interception of the Heathwall Pumping Station and South West Storm Relief CSOs and how they progressed through the site selection process is provided in Appendix 1.

2.2 Assessment of the long list sites 2.2.1 One long list of potential sites to intercept the Heathwall Pumping Station

and South West Storm Relief CSOs was created by conducting a desktop survey of the land in the vicinity of the existing sewers.

2.2.2 The Heathwall Pumping Station (CS16X) and South West Storm Relief (CS17X) CSOs are close together and were therefore considered together.

2.2.3 In total, five sites were included on the long list. The sites were assessed having regard to the high-level considerations set out in Table 2.2 of the Site selection methodology paper (hereafter referred to as SSMP Table 2.2), which included engineering (site size, site features, availability of a jetty/wharf, access and location (proximity to the sewer to be intercepted)), planning and environment (heritage, landscape/townscape, open space and ecology) and community and property (neighbouring land uses, site use, Special Land/Crown land and acquisition costs) considerations.


2 Phase one consultation preferred CSO site: Site selection process 2.2.4 Table 2.1 below provides a summary of the outcome of the SSMP

Table 2.2 assessment of the long list of sites considered for the interception of the Heathwall Pumping Station and South West Storm Relief CSOs. Sites that were identified to be the least constrained in light of the SSMP Table 2.2 considerations passed to the draft short list. This did not necessarily mean that these sites were ultimately judged to be suitable, but rather that no significant constraints were identified in relation to the high-level considerations set out in SSMP Table 2.2. Sites that were judged to be more constrained were not retained on the draft short list for more detailed assessment. The main rationale for excluding these sites at this stage is summarised below in Table 2.1.

Table 2.1 Long list to draft short list SSMP Table 2.2 assessment

Site ID Site name/description Recommendation and rationale

C16XA Foreshore, adjacent to Heathwall Pumping Station (partly overlaps C17XA)*

Recommendation: To draft short list.

C17XA Foreshore, adjacent to Middle Wharf (partly overlaps C16XA)*


C17XB Part of Heathwall Pumping Station and Middle Wharf*


C17XC Post office, Nine Elms Lane+ Recommendation: To draft short list.

C17XD Parking area, New Covent Garden Market+


NB: The site ID and site name/description were used as an internal mechanism to record and describe the site but were updated where necessary. Sites marked with * could potentially intercept both the Heathwall Pumping Station CSO (CS16X) and the South West Storm Relief CSO (CS17X), but sites marked with + could only intercept the South West Storm Relief CSO. Originally, sites were identified to intercept each CSO, which is why some sites overlap.

2.2.5 Of the five sites on the long list, all five were assessed as potentially suitable and passed to the draft short list.

2.3 Assessment of draft short list sites 2.3.1 The five draft short list sites identified for further assessment at the next

stage were: a. C16XA: Foreshore, adjacent to Heathwall Pumping Station (partly

overlaps C17XA) b. C17XA: Foreshore, adjacent to Heathwall Pumping Station (partly

overlaps C16XA) c. C17XB: Part of Heathwall Pumping Station and Middle Wharf d. C17XC: Post office, Nine Elms Lane e. C17XD: Parking area, New Covent Garden Market.

2.3.2 These sites were further assessed by the engineering, planning, environment, community, and property disciplines, having regard to the



considerations set out in Table 2.3 of the Site selection methodology paper (hereafter referred to as Table 2.3) which included: engineering (site size, distance and route to the river, jetty/wharf facilities, means of road/rail access, site features, site efficiency, tunnelling, systems engineering requirements and connection feasibility), planning and environment (planning applications/permissions, London Plan/UDP/LDF allocations or special policy areas, heritage designations, landscape/open space designations, ecological designation, transport and amenity), property (ownership of site, tenant on site, estimated acquisition cost, Crown land and special land, access and material transfer rights) and community (proximity to sensitive receptors, social, economic, health and equality considerations). This stage of the process built on the information gathered and the assessment undertaken at the long list stage but focussed on more detailed local considerations.

2.3.3 At this stage, we also consulted with each of the London local authorities along the route of the project and other pan-London stakeholders, such as the Environment Agency and English Heritage, to seek their views on the suitability of the sites for the short list.

2.3.4 Table 2.2 below summarises the outcome of the SSMP Table 2.3 assessment of the draft short list of sites. Sites that were assessed as being the least constrained in light of the SSMP Table 2.3 considerations were retained on the short list and passed to the next stage of assessment. This did not necessarily mean that a site was ultimately judged suitable, but rather that no significant constraints were identified in relation to the considerations set out at SSMP Table 2.3. Sites that were judged to be more constrained were not retained on the short list for more detailed assessment. The decision of whether or not to retain a site on the short list was taken at a multidisciplinary workshop. The main rationale for excluding sites at this stage is summarised below in Table 2.2.

Table 2.2 Draft short list to final short list SSMP Table 2.3 assessment


C16XA Foreshore, adjacent to Heathwall Pumping Station (partly overlaps C17XA)*

Recommendation: Retain on short list.

C17XA Foreshore, adjacent to Middle Wharf (partly overlaps C16XA)*


C17XB Part of Heathwall Pumping Station and Middle Wharf *


C17XC Post office, Nine Elms Lane+ Recommendation: Not to short list. Rationale: • Engineering: Use of this site would

require a very deep interception




(about 19m). • Property: The site would require

loss of parking affecting the post office’s business. This would result in a high acquisition cost.

• Community: It was likely that there would be a significant local economic impact due to the impact on the post office.

C17XD Parking area, New Covent Garden Market+

Recommendation: Not to short list. Rationale: • Engineering: Use of this site would

require a very deep interception (about 19m).

• Planning/Environment: Planning permission was approved in 2008 for a change in use from a bank to an educational facility.

• Property: Loss of parking at New Covent Garden Market would result in high acquisition costs.

• Community: There might be some impact on equalities considerations and the local community, and it was likely that there would be a significant local economic impact on the New Covent Garden Market.

NB: The site ID and site name/description were used as an internal mechanism to record and describe the site but were updated where necessary. Sites marked with * can potentially intercept both Heathwall Pumping Station (CS16X) and South West Storm Relief (CS17X), but sites marked with + can potentially only intercept South West Storm Relief (CS17X). Originally, sites were identified to intercept each CSO, so hence why some sites overlap.

2.3.5 Of the five sites on the draft short list, three were assessed as potentially suitable and passed to the final short list. Two sites did not proceed to the final short list.

2.4 Assessment of the final short list sites 2.4.1 The three sites identified for inclusion on the final short list and

assessment at the next stage were: a. C16XA: Foreshore, adjacent to Heathwall Pumping Station (partly

overlaps C17XA) b. C17XA: Foreshore, adjacent to Middle Wharf (partly overlaps C16XA) c. C17XB: Part of Heathwall Pumping Station and Middle Wharf.


2 Phase one consultation preferred CSO site: Site selection process 2.4.2 A site suitability report was prepared for each of the Final Shortlisted sites.

These reports contained an assessment of each site’s suitability, having regard to engineering, planning, environment, community and property considerations. At this stage in the process, sites were assessed in isolation with no comparison to other sites or regard to tunnelling strategy. Sites were evaluated by each discipline, using technical knowledge and professional judgement as appropriate, and assessed as suitable, less suitable or not suitable from that discipline’s perspective.

2.4.3 A summary of the conclusions of each discipline’s assessment from the site suitability reports is provided below.

C16XA: Foreshore, adjacent to Heathwall Pumping Station 2.4.4 Site C16XA is located in the foreshore of the River Thames, close to Nine

Elms Lane in the London Borough of Wandsworth. This site also partly overlaps C17XA.

2.4.5 The site adjoins a predominantly industrial area. The site is located to the northeast of the Thames Water Heathwall Pumping Station and the safeguarded Middle Wharf. Several houseboats and a restaurant are moored west of this site.

2.4.6 Engineering: The site was considered suitable as a CSO site because it is of adequate size and would have reasonable access direct from a major road through Thames Water-owned land.

2.4.7 Planning: On balance, the site was considered suitable as a CSO site. There were a number of applicable planning and environmental designations, but they would not be unacceptably affected. Furthermore, during and after the works, the structures would not be prominent in this industrial area.

2.4.8 Environment: Overall, the site was assessed as suitable as a CSO site. The site was considered likely to be suitable from the perspectives of transport, archaeology, built heritage and townscape, hydrogeology and air quality. However, the site was considered less suitable from the perspectives of surface water, ecology, flood risk, noise and land quality. Various mitigation measures would be required.

2.4.9 Socio-economic and community: The site was assessed as suitable as a CSO site. The greatest impact would be disruption experienced by the houseboats (Tideway Dock and Nine Elms Pier) and restaurant (the Battersea Barge) adjacent to the site. Mitigation would involve relocation, which might be difficult considering availability of mooring on the River Thames in London.

2.4.10 Property: The site was assessed as suitable as a CSO site as the acquisition costs were likely to be acceptable. However, a special ministerial procedure might be required, which could cause delays.

C17XA: Foreshore, adjacent to Middle Wharf 2.4.11 Site C17XA is located in the foreshore of the River Thames, close to Nine

Elms Lane in the London Borough of Wandsworth. This site also partly overlaps C16XA.


2 Phase one consultation preferred CSO site: Site selection process 2.4.12 The site adjoins a predominantly industrial area. It is located to the

northeast of the Thames Water Heathwall Pumping Station and the safeguarded Middle Wharf. Several houseboats and a restaurant are moored west of this site.

2.4.13 Engineering: The site was considered suitable as a CSO site because it is relatively unrestricted in size and shape and would have reasonable access direct from a major road.

2.4.14 Planning: On balance, the site was considered suitable as a CSO site. There were a number of applicable planning and environmental designations, but they would not be unacceptably affected. Furthermore, during and after the works, the structures would not be prominent in this industrial area.

2.4.15 Environment: Overall, the site was assessed as suitable as a CSO site. The site was considered likely to be suitable from the perspectives of transport, archaeology, built heritage and townscape, hydrogeology and air quality. However, the site was considered less suitable from the perspectives of surface water, ecology, flood risk, noise and land quality. Various mitigation measures would be required.

2.4.16 Socio-economic and community: The site was assessed as suitable as a CSO site. The greatest impact would be disruption experienced by the houseboats (Tideway Dock and Nine Elms Pier) and the restaurant (the Battersea Barge) adjacent to the site. Mitigation would involve relocation, which might be difficult considering the availability of mooring on the River Thames in London.

2.4.17 Property: The site was assessed as suitable as a CSO site as the acquisition costs were likely to be acceptable. However, a special ministerial procedure might be required, which could cause delays.

C17XB: Part of Heathwall Pumping Station and Middle Wharf

2.4.18 Site C17XB is located on part of the Heathwall Pumping Station site and the safeguarded Middle Wharf, which was formerly used as a concrete batching plant. The site is also adjacent to the River Thames in the London Borough of Wandsworth.

2.4.19 Immediately to the north of the site are the River Thames Foreshore and a jetty. To the east are a small area of open space and an eight-storey residential block known as Elm Quay. Opposite the site to the south are an office/factory and the Tideway Industrial Estate. To the west of the site are the Thames Water Heathwall Pumping Station and a Fed Ex building located on the Tideway Industrial Estate.

2.4.20 Engineering: The site was considered suitable as a CSO site because it is of adequate size with good road access.

2.4.21 Planning: On balance, the site was considered suitable as a CSO site. There were a number of applicable planning and environmental designations, but they would not be unacceptably affected. The site is



located on a safeguarded wharf which might provide the opportunity for river transport.

2.4.22 Environment: Overall, the site was assessed as suitable as a CSO site. The site was considered likely to be suitable from the perspectives of transport, archaeology, built heritage and townscape, water resources (both hydrogeology and surface water), ecology, flood risk and air quality. However, the site was considered less suitable from the perspectives of noise and land quality. Various mitigation measures would be required.

2.4.23 Socio-economic and community: The site was assessed as suitable as a CSO site. The greatest impact would be disruption experienced by the houseboats (Tideway Dock and Nine Elms Pier) and the restaurant (the Battersea Barge) adjacent to the site. Mitigation would involve relocation, which might be difficult considering the availability of mooring on the River Thames in London. It is unlikely that the use of the site would have a significant impact on the local community, given its existing use. Furthermore, the site has been decommissioned and cleared so it is unlikely that there would be impacts on the local economy.

2.4.24 Property: The site was assessed as suitable as a CSO site as the site is owned by Thames Water.

2.5 Phase one consultation preferred site 2.5.1 Following the completion of the site suitability reports, we held a

multidisciplinary workshop to compare the suitability of each of the shortlisted sites based on the site suitability report assessments and to recommend which site should be identified as the preferred site. The workshop identified C17XB: part of Heathwall Pumping Station and Middle Wharf as the most suitable site for the interception of the Heathwall Pumping Station CSO and South East Storm Relief CSO.

2.5.2 The CSO site (C17XB) was then combined with the main tunnel sites S79WH and S80WH (which partly overlap C17XB); and together these sites were collectively known as S79WH/S80WH/C17XB: Tideway Walk1 (please see Volume 13 for discussion on main tunnel sites in Zone S5 Battersea).

2.5.3 Therefore, S79WH/S80WH/C17XB: Tideway Walk was identified as the phase one consultation preferred site for interception of the South West Storm Relief CSO and the Heathwall Pumping Station CSO, in association with the main tunnel site use, for the following reasons (not in order of importance): a. Generally, C16XA/C17XA (overlapping foreshore sites with the drop

shaft constructed in the river) and C17XB (land-based site) were

1 The engineering details of how these CSOs would be dealt with in relation to the main tunnel shaft are complex. In summary, both interceptions would connect to the main tunnel, which would contain two drop shafts. There would be an intermediate shaft next to the South West Storm Relief CSO interception chamber, so the connecting culvert could pass under Heathwall Pumping Station to the main shaft.



considered suitable in engineering, planning, environmental, community and property terms. However, C16XA/C17XA as a foreshore site would introduce increased construction costs and health and safety risks associated with working in a river environment. It would also require the temporary and permanent structures to be located in the river foreshore, which would entail a loss of foreshore habitat. Therefore, site C17XB was preferred over C16XA/C17XA (the foreshore site) as a suitable and feasible land-based site available in this location, near to the route of these sewers.

b. C17XB is owned by Thames Water and includes Heathwall Pumping Station and Middle Wharf, so the proposed use of this site was consistent with the existing uses.

c. C17XB contains Middle Wharf, which is designated as a safeguarded wharf with jetty facilities. The wharf might provide an opportunity to export and import construction material via the River Thames, which would reduce the need for vehicular traffic to and from the site.

d. From a property point of view, both C16XA/C17XA and C17XB were considered suitable but, as the land-based site is owned by Thames Water, there would be no acquisition costs for C17XB.

2.5.4 Table 2.3 below sets out the preferred site and use. Table 2.3 Preferred site and use for phase one consultation

Site: S79WH/S80WH/C17XB: Tideway Walk Use: To intercept the Heathwall Pumping Station and South West Storm Relief CSOs and connect it to the main tunnel.


3 Phase two consultation preferred CSO site: Scheme development and site selection process


3.1 Introduction 3.1.1 This section explains how we implemented the Site selection methodology

paper in order to arrive at the preferred CSO site for phase two consultation. This stage took place from Winter 2010 to Autumn 2011.

3.1.2 Following phase one consultation and prior to phase two consultation, the site selection process comprised: a. a review of comments from phase one consultation b. consideration of any ongoing project design and/or new information c. a multidisciplinary optioneering workshop to identify the preferred CSO

site to intercept the Heathwall Pumping Station and South West Storm Relief CSOs for phase two consultation.

3.1.3 The assessments described in this section were based on the information available at the time and the related stage in the pre-application process.

3.1.4 A plan that illustrates all the sites considered for the interception of the Heathwall Pumping Station and South West Storm Relief CSOs is provided in Appendix 2.

3.2 Summary of phase one consultation feedback 3.2.1 Details of the consultation comments related to this site and our responses

are provided in the Report on phase one consultation. The main concerns raised relevant to site selection can be summarised as follows: a. impact on boat moorings and community severance b. impact on residential amenity c. impact on the planned regeneration of the area d. design of permanent proposals for the site e. impact on Cringle Dock Wharf.

3.2.2 The main comments received in support of the phase one consultation preferred site included: a. it is a brownfield and industrial site and area b. it would have less impact on existing heritage c. it has good transport infrastructure and would allow transport of

materials by barge d. it would reduce the impact on residential amenity e. the proposals for the site following construction are acceptable.


3 Phase two consultation preferred CSO site: Scheme development and site selection process 3.3 Back-check process 3.3.1 In addition to the consultation comments, further engagement with the

London Borough of Wandsworth and the landowner revealed that a large proportion of the Tideway Walk site was unavailable due to a major residential development that had been granted planning permission and demolition had commenced on site. However, the overall tunnelling strategy required a main tunnel site in the Battersea area. The distance between potential sites in this zone and the next set of potential sites to the east (Zone S6 Shad) was such that a main tunnel site in this zone was required to ensure that maximum recommended tunnelling distances were not exceeded, and it was necessary to change TBMs in this area. There is also a need to intercept the Heathwall Pumping Station and South West Storm Relief CSOs.

3.3.2 The new information and comments from consultees resulted in the need for a back-check to identify alternative locations for a main tunnel site and a CSO site. Due to the lack of land near the Heathwall Pumping Station, this was likely to mean that two separate sites would be needed, one for the main tunnel site (see Volume 13 – Kirtling Street, which became the preferred main tunnel site to replace Tideway Walk) and a second to intercept the two local CSOs. The site to connect the two CSOs to the main tunnel could be much smaller with fewer permanent structures so we believed that there was still potential for it to be located in the vicinity of the Heathwall Pumping Station.

3.3.3 This back-check involved a targeted repeat of each relevant stage of our site selection process to reconsider which site would be most suitable for the interception of the Heathwall Pumping Station and South West Storm Relief CSOs to divert flows to the main tunnel. The results from each stage of the back-check process are outlined below.

Assessment of the back-check long list 3.3.4 A number of potential CSO sites were identified in the vicinity of the two

CSOs. There was a choice between a foreshore site (adjacent to Heathwall Pumping Station and Middle Wharf) and a land-based site (Heathwall Pumping Station and Middle Wharf). The site areas and site IDs were simplified in order to make it easier to compare them. The following sites were assessed: a. C16XA: Foreshore (adjacent to Heathwall Pumping Station and Middle

Wharf) – previously C16XA and C17XA b. C16XB: Heathwall Pumping Station (includes Middle Wharf) –

previously part of C17XB. 3.3.5 Sites C17XA (to avoid overlapping foreshore sites) and C17XB (to avoid

overlapping land-based sites) were withdrawn and replaced by the new sites, as outlined above. This allowed us to draw a more straightforward comparison between building the drop shaft on a foreshore site or a land-based site, which were capable of intercepting both CSOs.


3 Phase two consultation preferred CSO site: Scheme development and site selection process 3.3.6 The back-check long list sites were assessed against the high-level

considerations set out in SSMP Table 2.2 which included engineering (site size, site features, availability of a jetty/wharf, access and location (proximity to the sewer to be intercepted), planning and environment (heritage, landscape/townscape, open space and ecology) and community and property (neighbouring land uses, site use, Special Land/Crown land and acquisition costs) considerations.

3.3.7 Table 3.1 below summarises the outcome of the back-check assessment of the back-check long list of sites. Sites that were assessed as the least constrained in light of the SSMP Table 2.2 considerations passed to the next stage of assessment. This did not necessarily mean that these sites were ultimately judged to be suitable, but rather that no significant constraints were identified in relation to the high-level considerations set out at SSMP Table 2.2. Sites that were judged to be more constrained did not pass to the back-check draft short list for more detailed assessment. The main rationale for excluding these sites at this stage is summarised in the table below.

Table 3.1 Long list to draft short list SSMP Table 2.2 assessment

Site ID Site name/description Recommendation and rationale C16XA Foreshore (adjacent to

Heathwall Pumping Station and Middle Wharf)


C16XB Heathwall Pumping Station (includes Middle Wharf)


NB: The site ID and site name/description were used as an internal mechanism to record and describe the site but were updated where necessary.

3.3.8 Of the two sites identified, both were assessed as potentially suitable and passed to the draft short list.

Assessment of the back-check draft short list sites 3.3.9 The two back-check draft shortlisted sites were further assessed by the

engineering, planning, environment, community, and property disciplines, having regard to the considerations set out in SSMP Table 2.3 which included: engineering (site size, distance and route to the river, jetty/wharf facilities, means of road/rail access, site features, site efficiency, tunnelling, systems engineering requirements and connection feasibility); planning and environment (planning applications/permissions, London Plan/UDP/LDF allocations or special policy areas, heritage designations, landscape/open space designations, ecological designation, transport and amenity); property (ownership of site, tenant on site, estimated acquisition cost, Crown land and special land, access and material transfer rights) and community (proximity to sensitive receptors, social, economic, health and equality considerations).

3.3.10 Table 3.2 below summarises the outcome of the back-check assessment of the draft short list of sites. Sites that were assessed as the least constrained in light of the SSMP Table 2.3 considerations were retained on the back-check short list to pass to the next stage of assessment. This



did not necessarily mean that a site was ultimately judged suitable, but rather that no significant constraints were identified in relation to the considerations set out at SSMP Table 2.3. Sites that were judged to be more constrained were not retained on the back-check short list for more detailed assessment.

3.3.11 The main rationale for excluding these sites at this stage is summarised below.

Table 3.2 Draft short list to final short list SSMP Table 2.3 assessment

Site ID Site name/description Recommendation and rationale C16XA Foreshore (adjacent to

Heathwall Pumping Station and Middle Wharf)


C16XB Heathwall Pumping Station (includes Middle Wharf)


NB: The site ID and site name/description were used as an internal mechanism to record and describe the site but were updated where necessary.

3.3.12 Of the two sites on the draft short list, both were assessed as potentially suitable and passed to the final short list.

Assessment of the back-check final short list sites 3.3.13 The two back-check final shortlisted sites identified for assessment at the

next stage were: a. C16XA: Foreshore (adjacent to Heathwall Pumping Station and Middle

Wharf) b. C16XB: Heathwall Pumping Station (includes Middle Wharf).

3.3.14 A site suitability report was prepared for the new back-check final short list sites and the site suitability reports for the phase one shortlisted sites were re-evaluated. C16XA: Foreshore (adjacent to Heathwall Pumping Station and Middle Wharf)

3.3.15 Although a number of development plan documents had been adopted since the site suitability report was completed, the updated policies did not affect the final planning assessment recommendation.

3.3.16 All other discipline recommendations remained unchanged (see Section 2). C16XB: Heathwall Pumping Station (includes Middle Wharf)

3.3.17 Site C16XB is located in the Nine Elms Industrial Area of the London Borough of Wandsworth. The site comprises a Thames Water pumping station and a vacant safeguarded wharf that contains an existing electrical substation and jetty.

3.3.18 The site is bounded to the north by the River Thames, it fronts onto Nine Elms Lane to the south, and is situated between the Tideway Industrial



Estate and Elm Quay. The wider area is industrial in character and consists of warehouse buildings, depots and office accommodation.

3.3.19 Engineering: The site was assessed as suitable as a CSO site because it is of adequate size, has good river access and available road access.

3.3.20 Planning: The site was assessed as suitable for a CSO site. There were a number of planning designations applicable to the site, but we considered that, with appropriate mitigation measures, it was unlikely that these designations would be unacceptably affected. Furthermore, part of the site was designated for the construction of the project. The eastern portion is a safeguarded wharf (Middle Wharf) and the works were likely to be acceptable for such a site, provided they did not impact on the future development potential of the site.

3.3.21 Environment: Overall, the site was assessed as suitable as a CSO site. The site was considered likely to be suitable from the perspectives of transport, archaeology, built heritage, townscape, hydrogeology, air quality and noise. However, the site was considered less suitable from the perspectives of surface water, flood risk, ecology and land quality. Various mitigation measures would be required.

3.3.22 Socio-economic and community: The site was assessed as suitable as a CSO site. There would be some impact on the houseboat community moored to the west of the site and the residents of apartments at Elm Quay given the location of the shaft. However, given the distance to those receptors, the impacts were unlikely to be significant.

3.3.23 Property: The site was assessed as suitable as a CSO site as the site is primarily owned by Thames Water. Furthermore, the area that is not in Thames Water’s ownership is undeveloped foreshore and therefore acquisition costs were likely to be acceptable. However, the foreshore and riverbed part of the worksite was likely to be Crown- or PLA-owned land. Crown land cannot be compulsorily purchased. If it were owned by the PLA, there were risks associated with acquiring land by compulsory purchase from another statutory undertaker.

3.4 Phase two consultation preferred site 3.4.1 Following the completion of the back-check process, we held a

multidisciplinary workshop to assess the suitability of a site to intercept both the Heathwall Pumping Station and South West Storm Relief CSOs. A foreshore site (C16XA) was compared to a land-based site (C16XB).

3.4.2 This workshop took into account the findings of all the site suitability reports and the feedback received during phase one consultation. On the basis of the assessments described above and professional judgement, it was agreed by all disciplines that C16XB: Heathwall Pumping Station should become the recommended phase two consultation preferred site for the interception by means of a combined drop shaft for both the Heathwall Pumping Station and South West Storm Relief CSOs. This meant that we believed this to be the most appropriate site, subject to



further engagement with stakeholders and further design development to verify that conclusion prior to phase two consultation.

3.4.3 In summary, C16XB Heathwall Pumping Station (including Middle Wharf) was identified as the most suitable site for the following reasons: a. C16XB is available and it is a suitable land-based site that would

reduce the impacts associated with working in the foreshore (C16XA). b. C16XB site would allow the interception of both CSOs and room for

the CSO drop shaft in one location, thereby minimising the impact of permanent works in the foreshore.

c. C16XB is owned by Thames Water. 3.4.4 The above points were based on the information available at the time and

the related stage in the pre-application process. The points therefore comprise a historic representation of the process prior to phase two consultation.

3.4.5 Table 3.3 below sets out the preferred site and use. Table 3.3 Preferred site and use for phase two consultation

Site: C16XB: Heathwall Pumping Station Use: To intercept the Heathwall Pumping Station and South West Storm Relief CSOs and connect it to the main tunnel.


4 Post phase two consultation: Review and confirmation of proposed CSO site for Section 48 publicity


4.1 Introduction to the review 4.1.1 This section explains how we implemented the requirement in the Site

selection methodology paper to review the preferred site following phase two consultation and prior to Section 48 publicity. This stage took place from Spring 2012 to Summer 2012.

4.1.2 The review at this stage of the site selection process comprised: a. a review of comments from phase two consultation b. consideration of any ongoing project design and/or new technical

information c. multidisciplinary reviews and workshops to identify the proposed CSO

sites and uses for Section 48 publicity. 4.1.3 The assessments described in this section were based on the information

available at the time and the related stage in the pre-application process. 4.1.4 A plan that illustrates all the sites considered for the interception of the

Heathwall Pumping Station and South West Storm Relief CSOs is provided in Appendix 3.

4.2 Summary of phase two consultation feedback 4.2.1 Details of the consultation comments related to this site and our responses

are provided in the Report on phase two consultation. The main concerns raised relevant to site selection can be summarised as follows: a. opposed in principle to the use of any foreshore structures along the

tidal Thames as this is likely to lead to a number of detrimental effects of flood risk management, biodiversity and recreation.

4.2.2 The main comments received in support of the phase two consultation preferred site included: a. support for the use of the preferred site b. the preferred site is more suitable than the shortlisted site in terms of

reducing the adverse impacts on archaeology c. no objection in principle in terms of navigational safety.

4.2.3 Having taken all comments received during phase two consultation into account, we still considered C16XB Heathwall Pumping Station the most suitable site to intercept of the Heathwall Pumping Station and South West Storm Relief CSOs.

4.2.4 We recognised the concerns that had been raised, including utilisation of the foreshore, and we took these into account when developing the



scheme further, including measures which could be put in place to minimise any significant potential impacts.

4.3 Consideration of project design or new information 4.3.1 The multidisciplinary review of this site confirmed that there was no new

information that would lead to any changes in circumstances. 4.3.2 Given that there are no changes in circumstances or new information with

relevance to site selection, we still considered C16XB: Heathwall Pumping Station the most suitable site to intercept of the Heathwall Pumping Station and South West Storm Relief CSOs.

4.4 Proposed site for Section 48 publicity 4.4.1 Having completed the site selection review described above, we held a

further multidisciplinary workshop prior to Section 48 publicity. On balance, the review process did not identify any considerations that would have caused us to change our preferred site from phase two consultation. Therefore, C16XB: Heathwall Pumping Station was identified as the proposed CSO site for Section 48 publicity for the following reasons (not in order of importance): a. C16XB is available and predominantly owned by Thames Water,

therefore reducing the property risk associated with development in the foreshore. As the majority of the site is land-based its use would also reduce the impacts associated with working in the foreshore compared to C16XA

b. C16XB would allow the interception of both CSOs and the creation of the drop shaft in one location, thereby minimising the impact of permanent works in the foreshore.

c. The Local Planning Authority’s Site Specific Allocations Document acknowledges the potential use of site C16XB for use by the project and the site is also partly designated as a safeguarded wharf. The proposed works would accord with these designations, although a small part of site lies in the river foreshore.

d. The use of C16XB would minimise works in the foreshore, which is designated as a Site of Metropolitan Importance for Nature Conservation.

4.4.2 Table 4.1 below sets out the proposed site and use. Table 4.1 Proposed site and use for Section 48 publicity



5 Post Section 48 publicity: Review and final selection of CSO site for the application


5.1 Introduction to the review 5.1.1 This section explains how we conducted a site selection review in order to

arrive at the final selection of sites to be included in the application. This stage took place during Autumn 2012.

5.1.2 The final review comprised: a. review of comments from Section 48 publicity b. consideration of any ongoing project design and/or new technical

information c. final multidisciplinary reviews and workshops to re-consider the

comparisons of sites and the rationale for selecting the CSO site for the application.

5.1.3 A plan that illustrates all the sites considered for the interception of the Heathwall Pumping Station and South West Storm Relief CSOs is provided in Appendix 4.

5.2 Summary of Section 48 publicity feedback 5.2.1 Details of the comments to Section 48 publicity related to this site and our

responses are provided in the Consultation Report. The main concerns raised relevant to site selection can be summarised as follows: a. No main objections, issues or concerns were received in respect of

site selection and alternative sites. 5.2.2 The main comments received in support of the proposed site included:

a. Support the use of the proposed site. b. Support review of sites that has been undertaken in the pre-

application process as this has resulted in reductions in the amount of land that needs to be acquired and in the impact on the townscape from new structures above ground.

5.2.3 Relevant Section 48 publicity comments were taken into account in the review of shortlisted CSO sites set out in Section 5.4 below.

5.3 Consideration of project design or new information 5.3.1 The review of this site confirmed that there was no new project design

and/or technical information relevant to site selection.



5.4 Final review of shortlisted CSO sites 5.4.1 As part of the final review process, all the phase two shortlisted sites for

this CSO were reviewed and compared following Section 48 publicity. 5.4.2 Below is the final list of shortlisted sites followed by a summary of the

points that distinguished between the sites (comparisons are not in order of importance): a. C16XA: Foreshore (drop shaft in the foreshore adjacent to Heathwall

Pumping Station and Middle Wharf) b. C16XB: Heathwall Pumping Station (includes Middle Wharf with the

drop shaft on land). 5.4.3 Foreshore sites are not generally preferred where viable land-based

alternatives exist due to increased health and safety risks, construction costs association with working in a river and impact to foreshore habitats. The river is designated as a Site of Metropolitan Importance for Nature Conservation, so use of this site would therefore have more impact on this designation than C16XB.

5.4.4 The London Borough of Wandworth’s adopted Site Specific Allocations Document acknowledges the potential use of site C16XB for use by the project and the site is also partly designated as a safeguarded wharf. The proposed works would accord with these designations, although a small part of site lies in the river foreshore.

5.4.5 C16XA and C16XB would use the river to transport materials from Middle Wharf during the construction phase, which would be consistent with the safeguarding of the wharf for cargo handling purposes. Once our temporary works are complete proposals would need to retain/reinstate the facilities required to ensure the wharf could be used for cargo handling purposes in the future.

5.4.6 Locating the shaft within Middle Wharf at site C16XB, would minimise the extent of construction that would be required in the foreshore, compared to C16XA. However, due to constraints around the pumping station, it would still be necessary to locate the interception chamber for the Heathwall Pumping Station CSO in the foreshore in front of the pumping station.

5.4.7 There is less property risk associated with the use of site C16XB as it is predominantly land-based and owned by Thames Water whereas site C16XA is located completely within the foreshore. However, both sites require some use of the foreshore so there is some acquisition risk, due to the need for agreements to be reached with the Crown Estate and Port of London Authority; although this risk would be much greater for site C16XA.

5.5 Selected site for the application 5.5.1 In summary, we reviewed and considered:

a. Section 48 publicity feedback



b. any relevant changes and/or new information c. shortlisted site comparisons.

5.5.2 The final site selection review described above, culminated in a multidisciplinary workshop following Section 48 publicity. On balance, the review process did not identify any new considerations that would have caused us to change our proposed site from Section 48 publicity. Therefore, C16XB: Heathwall Pumping Station was selected as the CSO site for the application for the following reasons (not in order of importance): a. London Borough of Wandworth’s Site Specific Allocations Document

acknowledges the potential use of site C16XB for use as part of the project and the site is also partly designated as a safeguarded wharf. The proposed works would accord with these designations, although a small part of site lies in the river foreshore.

b. The site is available and predominantly owned by Thames Water, therefore reducing the property risk associated with development in the foreshore. As the majority of the site is land-based its use would also reduce the impacts associated with working in the foreshore.

c. The site can accommodate the interception of both CSOs and the creation of the drop shaft in one location, thereby minimising the impact of permanent works in the foreshore, which is designated as a Site of Metropolitan Importance for Nature Conservation.

5.5.3 Table 5.1 below sets out the selected site and use. Table 5.1 Selected site and use for the application



Appendices

Appendix 1


Appendices



#

!(

Heathwall Pumping Station

CS16X

WANDSWORTH

CITY OF WESTMINSTER

C16XA

FOR INFORMATION

10 0 105 m

LocationCS16XHeathwall Pumping StationDocument InformationPhase oneCSO sites 1Pl04-SS-0255717 Dec 2012

Scale 1 : 1,000 at A3

±Keyplan:

Key

Local authority boundary (OS)

# Pumping Station

!( CSO directly controlledSite Selection

Not a preferred site

Mapping reproduced by permission of OrdnanceSurvey on behalf of HMSO. © Crown Copyright andDatabase right 2012. All rights reserved. OrdnanceSurvey licence number 100019345

© Thames Water Utilities Ltd 2008

#

!(


CS17X

WANDSWORTH

CITY OF WESTMINSTER

C17XC

C17XD

C17XA

C17XB

FOR INFORMATION

20 0 2010 m

LocationCS17XSouth West Storm ReliefDocument InformationPhase oneCSO sites 1PL04-SS-0255817 Dec 2012

Scale 1 : 2,000 at A3

±Keyplan:

Key


# Pumping Station


No at Table 2.3Preferred site on thepreferred tunnel routeNot a preferred site



Appendices

Appendix 2


Appendices



#

!( !(

C17XC

C17XD

C16XB

C16XA

CS17XCS16X

WANDSWORTH

LAMBETH

CITY OF WESTMINSTER


FOR INFORMATION

50 0 5025 m

LocationCS16X, CS17XHeathwall Pumping StationSouth West Storm ReliefDocument InformationPhase twoCSO sites 1PL04-SS-0246922 Nov 2012

Scale 1 : 2,500 at A3

±Keyplan:

Key


# Pumping Station


No 'No' at Table 2.2

No at Table 2.3Preferred site for thepreferred tunnel routeNot a preferred site



NoteSite C17XA and C17XB have been retired

Appendices

Appendix 3


Appendices



C17XC

C17XD

C16XB

C16XA

CS17XCS16X

WANDSWORTH

LAMBETH

CITY OF WESTMINSTER


FOR INFORMATION

50 0 5025 m

LocationCS16X - Heathwall Pumping StationCS17X - South West Storm ReliefDocument InformationSection 48 publicityCSO sites

1PL04-SS-0258103 Jan 2013

Scale 1 : 2,500 at A3

Keyplan:



Key


Pumping Station

CSO directly controlledSite Selection

No at Table 2.3Proposed site for theproposed tunnel routeNot a proposed site

NoteSites C17XA and C17XB have been retired

Appendices

Appendix 4


Appendices


Final Report on Site Selection Process Volume 14: Heathwall Pumping Station

C17XC

C17XD

C16XB

C16XA

CS17XCS16X

WANDSWORTH

LAMBETH

CITY OF WESTMINSTER


FOR INFORMATION

50 0 5025 m

LocationCS16X - Heathwall Pumping StationCS17X - South West Storm ReliefDocument InformationSubmission of the applicationCSO sites

1PL04-SS-0258203 Jan 2013

Scale 1 : 2,500 at A3

Keyplan:



Key


Pumping Station

CSO directly controlledSite Selection

No at Table 2.3

Selected site

Not a selected site

NoteSites C17XA and C17XB have been retired

This page is intentionally blank

Copyright notice Copyright © Thames Water Utilities Limited January 2013. All rights reserved. Any plans, drawings, designs and materials (materials) submitted by Thames Water Utilities Limited (Thames Water) as part of this application for Development Consent to the Planning Inspectorate are protected by copyright. You may only use this material (including making copies of it) in order to (a) inspect those plans, drawings, designs and materials at a more convenient time or place; or (b) to facilitate the exercise of a right to participate in the pre-examination or examination stages of the application which is available under the Planning Act 2008 and related regulations. Use for any other purpose is prohibited and further copies must not be made without the prior written consent of Thames Water. Thames Water Utilities LimitedClearwater Court, Vastern Road, Reading RG1 8DB The Thames Water logo and Thames Tideway Tunnel logo are © Thames Water Utilities Limited. All rights reserved. DCO-DT-000-ZZZZZ-070500

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